In recent years, as one kind of medical or health information, medical records of individual patients, for example, have been converted into electronic ones, and the electronic medical records stored in databases have been used widely.
Note that the electronic medical records is used as an example below. And the electronic medical records may be the electronic health records or the personal health records, for example.
The electronic medical records are used to store diagnostic information for individual patients, but are also secondarily usable as a database of cases, for example. In the secondary use, the electronic medical records are used to improve the quality of medical service through analysis of similar cases.
In the case of secondary use of the electronic medical records, a keyword to be searched for (for example, a disease name) is inputted, and medical records (the full-text documents of the electronic medical records) containing the inputted keyword are searched out from the database (Japanese Patent Application Publication No. 2000-293599).
However, even if patients have almost the same symptoms and receive almost the same prescriptions-treatments, different disease names are sometimes entered in the medical records depending on judgments by medical doctors. Such difference can be recognized as so-called “variations in disease name entry.” For example, “acute bronchitis”, “acute sinusitis” and “asthma” can be cited as one example of “variations in disease name entry”.
In such a case, when “acute bronchitis” is inputted as a keyword for the secondary use of the electronic medical records, medical records entered with “acute bronchitis” can be searched out, but medical records entered not with “acute bronchitis” but with “acute sinusitis” or “asthma” cannot be searched out. In other words, this way of search is incapable of searching out electronic medical records containing disease names supposed to be medically related to the disease name inputted as the keyword.
Moreover, in terms of “variations,” there is a case where two or more diseases having completely different disease names can be judged as being medically related to each other from the viewpoint of prescription-treatment, because for example the diseases are provided with almost the same prescription-treatment.